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curs_termcap(3X)					      curs_termcap(3X)

       PC, UP, BC, ospeed, tgetent, tgetflag, tgetnum, tgetstr,	tgoto, tputs -
       direct curses interface to the terminfo capability database

       #include	<curses.h>
       #include	<term.h>

       extern char PC;
       extern char * UP;
       extern char * BC;
       extern short ospeed;

       int tgetent(char	*bp, const char	*name);
       int tgetflag(char *id);
       int tgetnum(char	*id);
       char *tgetstr(char *id, char **area);
       char *tgoto(const char *cap, int	col, int row);
       int tputs(const char *str, int affcnt, int (*putc)(int));

       These routines are included as a	conversion aid for programs  that  use
       the  termcap  library.	Their parameters are the same and the routines
       are emulated using the terminfo database.  Thus,	they can only be  used
       to  query  the  capabilities  of	entries	for which a terminfo entry has
       been compiled.

       The tgetent routine loads the entry for name.  It returns:

	  1  on	success,

	  0  if	there is no such entry (or that	it is a	generic	 type,	having
	     too little	information for	curses applications to run), and

	  -1 if	the terminfo database could not	be found.

       This differs from the termcap library in	two ways:

	  o   The  emulation  ignores  the buffer pointer bp.  The termcap li-
	      brary would store	a copy of the terminal description in the area
	      referenced  by this pointer.  However, ncurses stores its	termi-
	      nal descriptions in compiled binary form,	which is not the  same

	  o   There is a difference in return codes.  The termcap library does
	      not check	if the terminal	description is marked with the generic
	      capability,  or  if the terminal description has cursor-address-

       The tgetflag routine gets the boolean entry for id, or zero  if	it  is
       not available.

       The  tgetnum  routine gets the numeric entry for	id, or -1 if it	is not

       The tgetstr routine returns the string entry for	id, or zero if	it  is
       not  available.	 Use  tputs to output the returned string.  The	return
       value will also be copied to the	buffer pointed to  by  area,  and  the
       area value will be updated to point past	the null ending	this value.

       Only  the first two characters of the id	parameter of tgetflag, tgetnum
       and tgetstr are compared	in lookups.

       The tgoto routine instantiates the parameters into the given  capabili-
       ty.  The	output from this routine is to be passed to tputs.

       The  tputs  routine  is described on the	curs_terminfo(3X) manual page.
       It can retrieve capabilities by either termcap or terminfo name.

       The variables PC, UP and	BC are set by tgetent to the terminfo  entry's
       data for	pad_char, cursor_up and	backspace_if_not_bs, respectively.  UP
       is not used by ncurses.	PC is used in the tdelay_output	function.   BC
       is  used	in the tgoto emulation.	 The variable ospeed is	set by ncurses
       in a system-specific coding to reflect the terminal speed.

       Except where explicitly noted, routines that return an  integer	return
       ERR  upon  failure  and OK (SVr4	only specifies "an integer value other
       than ERR") upon successful completion.

       Routines	that return pointers return NULL on error.

       If you call tgetstr to fetch ca or any other parameterized  string,  be
       aware  that it will be returned in terminfo notation, not the older and
       not-quite-compatible termcap notation.  This will not cause problems if
       all  you	do with	it is call tgoto or tparm, which both expand terminfo-
       style strings as	terminfo.  (The	tgoto function,	if configured to  sup-
       port  termcap,  will  check  if	the string is indeed terminfo-style by
       looking for "%p"	parameters or "$<..>" delays, and  invoke  a  termcap-
       style parser if the string does not appear to be	terminfo).

       Because	terminfo  conventions for representing padding in string capa-
       bilities	differ from termcap's, tputs("50"); will  put  out  a  literal
       "50" rather than	busy-waiting for 50 milliseconds.  Cope	with it.

       Note  that termcap has nothing analogous	to terminfo's sgr string.  One
       consequence of this is that termcap applications	 assume	 me  (terminfo
       sgr0)  does not reset the alternate character set.  This	implementation
       checks for, and modifies	the data shown to the termcap interface	to ac-
       commodate termcap's limitation in this respect.

       The  XSI	 Curses	standard, Issue	4 describes these functions.  However,
       they are	marked TO BE WITHDRAWN and may be removed in future versions.

       Neither the XSI Curses standard nor the SVr4 man	pages  documented  the
       return  values  of tgetent correctly, though all	three were in fact re-
       turned ever since SVr1.	In particular, an omission in the  XSI	Curses
       documentation  has  been	misinterpreted to mean that tgetent returns OK
       or ERR.	Because	the purpose of these functions is to provide  compati-
       bility  with the	termcap	library, that is a defect in XCurses, Issue 4,
       Version 2 rather	than in	ncurses.

       External	variables are provided for support of certain termcap applica-
       tions.  However,	termcap	applications' use of those variables is	poorly
       documented, e.g., not distinguishing between input and output.  In par-
       ticular,	 some  applications  are reported to declare and/or modify os-

       The comment that	only the first two characters of the id	parameter  are
       used escapes many application developers.  The original BSD 4.2 termcap
       library (and historical relics thereof) did not require a trailing null
       NUL  on	the  parameter	name  passed to	tgetstr, tgetnum and tgetflag.
       Some applications assume	that the termcap interface  does  not  require
       the trailing NUL	for the	parameter name.	 Taking	into account these is-

       o   As a	special	case,  tgetflag	 matched  against  a  single-character
	   identifier  provided	 that  was at the end of the terminal descrip-
	   tion.  You should not rely upon this	behavior in portable programs.
	   This	 implementation	disallows matches against single-character ca-
	   pability names.

       o   This	implementation disallows  matches  by  the  termcap  interface
	   against extended capability names which are longer than two charac-

       curses(3X), terminfo(5),	term_variables(3X), putc(3).



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